Various United States patents have proposed sash guides incorporating diagonal flexible flanges employed to produce resilient force bearing against window sashes when deflected by installation of the sash. Sylvan U.S. Pat. No. 2,244,739 shows rolled sheet metal sash guides provided with a long diagonal tongue 16 extending from the outside corner of the sash guide inwardly toward the edge surface of the window sash. Sylvan's tongue is employed for balancing the sash and also for providing a weatherstripping action. In addition, the inner and outer terminal flanges of Sylvan's rolled metal section sash guide are resilient and thus hold the sash guide in place in the jamb in which the weatherstrip is located, but the resilience of these inner and outer flanges of Sylvan's sash guide does not apply any resilient force against the sash.
Resilient "Z" cross-section or "U" cross-section rolled sheet metal sash guide supports are shown in Gardner, Jr., U.S. Pat. No. 2,613,403, and resilient "Z" cross-section leaf spring weatherstripping material is shown in Dennis, U.S. Pat. No. 1,666,327; Blessin, U.S. Pat. No. 1,976,767; and Beil, U.S. Pat. No. 2,541,325. Resilient leaf spring sash guides employed for weatherstripping are shown in Robinson, U.S. Pat. No. 2,192,776; Mears, Jr., U.S. Pat. No. 3,269,062 and Hettinger, U.S. Pat. No. 2,775,795. All these patents apply resilient force along the edge surfaces of the sliding sash unit, rather than against the face of the sash. For this reason the prior art resilient weatherstripping sash balances permit lateral rocking play of the sash sidewise between two opposing resilient leaf spring flanges, and precise alignment and positioning of the sash is not possible with these prior art proposals.
With the present invention, direct diagonal resilient flanges apply pressure against a face of each sash along its vertical edge, urging the sash outwardly toward the outer fixed flange of the unitary sash guide and thus assuring its precise positioning without rocking or lateral play, while still achieving the advantages of resilient balancing and weatherstripping.